The Republican establishment has flexed its muscle in New Hampshire's presidential primaries for years. But in the unpredictable 2016 election, the state's standard political playbook faces challenges on two fronts.

Donald Trump's brash brand of populism is resonating with voters, and he's sustained a commanding lead in statewide preference polls for months. While several experienced politicians are well-liked, some party elites fear none will emerge as a consensus choice in time for the Feb. 9 primary, allowing Trump to win a plurality.

Kasich is competing most directly for support with New Jersey Gov. Chris Christie, former Florida Gov. Jeb Bush, and Florida Sen. Marco Rubio. Some centrist voters are fond of former Hewlett-Packard chief executive Carly Fiorina, but she is lagging behind the others.

A decisive victory in New Hampshire could reset a race dominated by Trump's unexpected durability. A weak showing would leave the establishment – generally understood to mean party leaders and insiders, mainstream donors and other influential figures who avoid the ideological extreme – with few options for a quick rebound.

The primary is sandwiched between contests in Iowa and South Carolina that favor conservatives. Centrist candidates will have to survive the Southern states that vote in the delegate-rich contests March 1 – Alabama, Arkansas, Georgia, Oklahoma, Tennessee, Texas and Virginia – before the race turns to more hospitable territory.

With less than two months until voting begins, some in New Hampshire's establishment see Christie as best-positioned to carry their presidential hopes out of New England. Christie has been a constant presence in New Hampshire for months, despite being largely ignored in national political circles, and has begun to pull in big endorsements.

"The excitement is with Governor Christie," said Jeb Bradley, the state Senate majority leader. Bradley endorsed Christie this month and said that among the experienced politicians running, "he represents the best chance to win."

Trump, a billionaire real estate mogul and reality television star, has shown little sympathy for the establishment's woes.

"I'm sorry I did this to you, but you got to get used to it," Trump said on "Fox News Sunday."

Republican leaders are worried about more than Trump. Some are equally wary of Texas Sen. Ted Cruz, an uncompromising conservative deemed unelectable as president by some GOP leaders, ultimately siphoning off Trump's support.

Even if Christie's standing strengthens, it's unlikely he can clear the field before the primary. Kasich and Bush are largely staking their bids on New Hampshire, where they are spending significant time and money. Rubio has endeared himself to more mainstream Republicans despite being ushered into office as part of the 2010 tea party wave. His advisers believe he can pull support from a broader pool of voters than can the three governors.

"People who have traditionally been active in the party are spread across a whole series of major candidates," said Judd Gregg, a Bush supporter and former US senator from New Hampshire. It's not like 2012, Gregg said, when most officeholders past and present backed Mitt Romney, the eventual nominee.

To Fergus Cullen, a former New Hampshire GOP chairman, the establishment candidates are "all so clustered that anyone can win that bracket."

So far, Republican operatives – some insisting on anonymity to discuss private conversations – say there is no organized effort to persuade one of those candidates to leave the race before the primary in order to narrow voters' choices. But there have been preliminary discussions about what to do if four or five of those candidates finish within a few percentage points of each other in New Hampshire and all want to stay in the race.

Republicans have discussed asking a party leader such as Romney or US House Speaker Paul Ryan, R-Wis., to step in at that point and help broker exits for some candidates. These strategists said Romney and Ryan have not been approached about doing that and probably wouldn't be until after the primary.

Cullen said he hopes the whittling down happens "organically." He suggested that even if the experienced politicians finished bunched together, those at the bottom may have no choice but to step aside.

"A pretty good candidate is going to finish sixth or seventh in New Hampshire," he said.